A firefighter was killed battling the two fires known as the Mendocino Complex fire, the California Department of Forestry and Fire Protection said in a statement Monday.

Jonathan Cox, the Cal Fire battalion chief for Northern California, confirmed the death Monday evening but said the name would not be released until next of kin had been notified. Fire officials said he was from Utah and was on the fire line Monday when he was injured. He was rushed to a hospital, where he died.

The death marks the sixth firefighter killed in California wildfires this year. This is the first fatality caused by the Mendocino Complex Fire north of Clear Lake.

Cal Fire and U.S. Forest Service commanders said in a statement that they “are deeply saddened to report the death.”

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Authorities say a Utah firefighter died battling the largest recorded blaze in California history. Fire officials say the man died Monday night at a hospital after he was injured at the site of the Mendocino Complex fire north of San Francisco. (Aug. 14)

Media: Associated Press

“Fact finding on the accident is ongoing and notification of the next of kin is in progress,” the statement Monday night said. “More information will be released as it becomes available.”

The Mendocino Complex has burned 349,890 acres in Colusa, Mendocino and Lake counties and has become the largest fire in California history. The complex comprises the River fire, which has been contained at 48,920 acres, and the 300,970-acre Ranch fire that started northeast of Ukiah and is currently 59 percent contained.

The monstrous fire is one of an unprecedented series of large, deadly and destructive fires that have raged through California over the past month, exposing astonished firefighting crews to things rarely if ever seen before, including pyro-cumulus clouds reaching into the stratosphere and powerful fire tornadoes.